A mouse is used to control a cursor on a computer screen in order to operate the computer. A roller of the mouse is one kind of button that is frequently used by the user of the computer. For example, by rotating the roller, the function of browsing web pages or moving the cursor can be achieved. Alternatively, by pressing the roller, a middle button signal is generated or the function of switching to a different operation mode is achieved.
For increasing the convenience and comfort of operating the roller, a roller module of an input device is disclosed in Taiwanese Patent No. 1448928. In the roller module, a recess or a hollow slot of the roller is equipped with one or two different toothed surfaces. When a swinging arm is contacted with one of the toothed surfaces, the rotation of the roller generates different tactile feels. Moreover, a hyper-fast roller module of a mouse is disclosed in Taiwanese Patent No. M498914. A tooth part and a stopping rod are installed in the roller module. In case that the stopping rod is pushed by a torsion spring, the stopping rod is in close contact with the tooth part. When a button linked with the stopping rod is operated by the user, the roller is switched between a hyper-fast scrolling mode and an ordinary scrolling mode. However, the conventional technologies still have some drawbacks. For example, since the mechanism for allowing the mouse to generate more tactile feels is usually very complicated, the layout of other components within the mouse is adversely affected and the yield of the mouse is reduced. Moreover, since only one or two tactile feels are provided, the conventional mouse cannot meet the user's requirements.
For meeting the requirements of different users, there is a need of providing a roller module with a simplified structure and capable of generating plural tactile feels.